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Discussion Starter #1
i have 1998 foreman 450 it is blowing gas into air box when trying to crank if you remove spark plug it stops valves r adjusted properly timing is on carb was cleaned and adjusted by honda dealer exhaust is not cloged what could it be any suggestions would help
 

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Will it fire or is it just filling the air box? When did it start doing this did it sit for awhile or was it overnight.
 

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It blows fuel into the airbox because the intake is the only place for the compression to escape if you take out the plug you have created anothe escape route, therefore it doesn't exhaust fuel into the airbox. I'm going to say you do have a timing issue even though the dealer did the valve adjustment, nobody is perfect even the dealer can make a mistake.
I think I would take off the valve covers and check for myself the valve adjustment. get it to TDC and loosen the valves up and readjust them to spec and see what you got then. If that doesn't work you may want to look at the carb for issues. Like Saber asked how long has it sat and did it just start this issue, and does it fire the plug?
 

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Discussion Starter #4
the plug fires but theres no gas getting to the plug it was running fine it just cut off and has not started since i was wondering if it was a burnt valve just checked the timing and valves they seem to be right
 

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Did you pull the head and check to see if your cam is aligned properly it really sounds like you skipped some teeth Bro.
 

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Discussion Starter #6 (Edited)
im thinking you might be right but i dont understand how pulling the head will tell me if i skipped timing my service manual shows timing chain is in the front cover so if im reading right i have to pull engine and seperate to check timing chain ps any help would be appriciated dealer says from this point the only way to fix is to buy new motor would like to get running to prove a point to them
 

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Yeah your right my cam is in the head yours isn't pull the cover check your allignment.
 

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...even the dealer can make a mistake...
:eek:

No! NO, NO, NO! I refuse to believe this. I'm shocked you would even say such a thing.
 

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Discussion Starter #10
just wanted to say thank you so much for taking the time and offering your advice sunday i will start to tear down and see the damage so ill let yall know what i find thank you again
 

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Please spare me... you work on your own bikes don't you? I admit some of the guys in the dealerships are good but in past experience I always get stuck with the wingnut who thinks a new sparkplug will fix anything.



:eek:

No! NO, NO, NO! I refuse to believe this. I'm shocked you would even say such a thing.
 

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before doing anything do a compression test ... it's easy and tells you if there is compression and how much. then a leak-down test if neccesary. The only thing to remove is a spark plug............
 

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To do a leak down you will need it to be TDC then add air and listen if you have air coming out of the exaust or manafold that could indacate a bent or bernt valve. But be sure its top dead center tdc
 

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then next pull the timing alignment caps and the valve cover caps. when you pull it over manually, you should see the valves open and close, compression stoke etc. aligned with the timing marks on the flywheel.....super easy without alot of extra teardown...
 

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Haha more than that... balancing shafts too. Then you have to worry about your damn auto belt tensioner unless your smart and got a manual belt tensioner. Crank sensor crank and cam seals if your working on DOHC and or vtec head. If vtec you have to be 150% correct on the position of the cam or vtec will fail thus burring all your oil and seizing the engine or locking up the whole head while engaging vtec and dropping valves ....I can go on and on. Carb timing is a walk in the park compared to PGFI...especially when your working with more than one cyl.
 

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haha yeah thos jap's have tiny hands man!
 
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